Complete Roguelike Tutorial, using python+libtcod, part 8 code

This is part of a series of tutorials; the main page can be found here. The tutorial uses libtcod version 1.6.0 and above. If you choose to use 1.5.1, you can find the old version here. If you choose to use 1.5.0, you can find the old version here.

Items and inventory

import libtcodpy as libtcod
import math
import textwrap
 
#actual size of the window
SCREEN_WIDTH = 80
SCREEN_HEIGHT = 50
 
#size of the map
MAP_WIDTH = 80
MAP_HEIGHT = 43
 
#sizes and coordinates relevant for the GUI
BAR_WIDTH = 20
PANEL_HEIGHT = 7
PANEL_Y = SCREEN_HEIGHT - PANEL_HEIGHT
MSG_X = BAR_WIDTH + 2
MSG_WIDTH = SCREEN_WIDTH - BAR_WIDTH - 2
MSG_HEIGHT = PANEL_HEIGHT - 1
INVENTORY_WIDTH = 50
 
#parameters for dungeon generator
ROOM_MAX_SIZE = 10
ROOM_MIN_SIZE = 6
MAX_ROOMS = 30
MAX_ROOM_MONSTERS = 3
MAX_ROOM_ITEMS = 2
 
#spell values
HEAL_AMOUNT = 4
 
 
FOV_ALGO = 0  #default FOV algorithm
FOV_LIGHT_WALLS = True  #light walls or not
TORCH_RADIUS = 10
 
LIMIT_FPS = 20  #20 frames-per-second maximum
 
 
color_dark_wall = libtcod.Color(0, 0, 100)
color_light_wall = libtcod.Color(130, 110, 50)
color_dark_ground = libtcod.Color(50, 50, 150)
color_light_ground = libtcod.Color(200, 180, 50)
 
 
class Tile:
    #a tile of the map and its properties
    def __init__(self, blocked, block_sight = None):
        self.blocked = blocked
 
        #all tiles start unexplored
        self.explored = False
 
        #by default, if a tile is blocked, it also blocks sight
        if block_sight is None: block_sight = blocked
        self.block_sight = block_sight
 
class Rect:
    #a rectangle on the map. used to characterize a room.
    def __init__(self, x, y, w, h):
        self.x1 = x
        self.y1 = y
        self.x2 = x + w
        self.y2 = y + h
 
    def center(self):
        center_x = (self.x1 + self.x2) / 2
        center_y = (self.y1 + self.y2) / 2
        return (center_x, center_y)
 
    def intersect(self, other):
        #returns true if this rectangle intersects with another one
        return (self.x1 <= other.x2 and self.x2 >= other.x1 and
                self.y1 <= other.y2 and self.y2 >= other.y1)
 
class Object:
    #this is a generic object: the player, a monster, an item, the stairs...
    #it's always represented by a character on screen.
    def __init__(self, x, y, char, name, color, blocks=False, fighter=None, ai=None, item=None):
        self.x = x
        self.y = y
        self.char = char
        self.name = name
        self.color = color
        self.blocks = blocks
        self.fighter = fighter
        if self.fighter:  #let the fighter component know who owns it
            self.fighter.owner = self
 
        self.ai = ai
        if self.ai:  #let the AI component know who owns it
            self.ai.owner = self
 
        self.item = item
        if self.item:  #let the Item component know who owns it
            self.item.owner = self
 
    def move(self, dx, dy):
        #move by the given amount, if the destination is not blocked
        if not is_blocked(self.x + dx, self.y + dy):
            self.x += dx
            self.y += dy
 
    def move_towards(self, target_x, target_y):
        #vector from this object to the target, and distance
        dx = target_x - self.x
        dy = target_y - self.y
        distance = math.sqrt(dx ** 2 + dy ** 2)
 
        #normalize it to length 1 (preserving direction), then round it and
        #convert to integer so the movement is restricted to the map grid
        dx = int(round(dx / distance))
        dy = int(round(dy / distance))
        self.move(dx, dy)
 
    def distance_to(self, other):
        #return the distance to another object
        dx = other.x - self.x
        dy = other.y - self.y
        return math.sqrt(dx ** 2 + dy ** 2)
 
    def send_to_back(self):
        #make this object be drawn first, so all others appear above it if they're in the same tile.
        global objects
        objects.remove(self)
        objects.insert(0, self)
 
    def draw(self):
        #only show if it's visible to the player
        if libtcod.map_is_in_fov(fov_map, self.x, self.y):
            #set the color and then draw the character that represents this object at its position
            libtcod.console_set_default_foreground(con, self.color)
            libtcod.console_put_char(con, self.x, self.y, self.char, libtcod.BKGND_NONE)
 
    def clear(self):
        #erase the character that represents this object
        libtcod.console_put_char(con, self.x, self.y, ' ', libtcod.BKGND_NONE)
 
 
class Fighter:
    #combat-related properties and methods (monster, player, NPC).
    def __init__(self, hp, defense, power, death_function=None):
        self.max_hp = hp
        self.hp = hp
        self.defense = defense
        self.power = power
        self.death_function = death_function
 
    def attack(self, target):
        #a simple formula for attack damage
        damage = self.power - target.fighter.defense
 
        if damage > 0:
            #make the target take some damage
            message(self.owner.name.capitalize() + ' attacks ' + target.name + ' for ' + str(damage) + ' hit points.')
            target.fighter.take_damage(damage)
        else:
            message(self.owner.name.capitalize() + ' attacks ' + target.name + ' but it has no effect!')
 
    def take_damage(self, damage):
        #apply damage if possible
        if damage > 0:
            self.hp -= damage
 
            #check for death. if there's a death function, call it
            if self.hp <= 0:
                function = self.death_function
                if function is not None:
                    function(self.owner)
 
    def heal(self, amount):
        #heal by the given amount, without going over the maximum
        self.hp += amount
        if self.hp > self.max_hp:
            self.hp = self.max_hp

class BasicMonster:
    #AI for a basic monster.
    def take_turn(self):
        #a basic monster takes its turn. if you can see it, it can see you
        monster = self.owner
        if libtcod.map_is_in_fov(fov_map, monster.x, monster.y):
 
            #move towards player if far away
            if monster.distance_to(player) >= 2:
                monster.move_towards(player.x, player.y)
 
            #close enough, attack! (if the player is still alive.)
            elif player.fighter.hp > 0:
                monster.fighter.attack(player)


class Item:
    #an item that can be picked up and used.
    def __init__(self, use_function=None):
        self.use_function = use_function
 
    def pick_up(self):
        #add to the player's inventory and remove from the map
        if len(inventory) >= 26:
            message('Your inventory is full, cannot pick up ' + self.owner.name + '.', libtcod.red)
        else:
            inventory.append(self.owner)
            objects.remove(self.owner)
            message('You picked up a ' + self.owner.name + '!', libtcod.green)
 
    def use(self):
        #just call the "use_function" if it is defined
        if self.use_function is None:
            message('The ' + self.owner.name + ' cannot be used.')
        else:
            if self.use_function() != 'cancelled':
                inventory.remove(self.owner)  #destroy after use, unless it was cancelled for some reason
 
def is_blocked(x, y):
    #first test the map tile
    if map[x][y].blocked:
        return True
 
    #now check for any blocking objects
    for object in objects:
        if object.blocks and object.x == x and object.y == y:
            return True
 
    return False
 
def create_room(room):
    global map
    #go through the tiles in the rectangle and make them passable
    for x in range(room.x1 + 1, room.x2):
        for y in range(room.y1 + 1, room.y2):
            map[x][y].blocked = False
            map[x][y].block_sight = False
 
def create_h_tunnel(x1, x2, y):
    global map
    #horizontal tunnel. min() and max() are used in case x1>x2
    for x in range(min(x1, x2), max(x1, x2) + 1):
        map[x][y].blocked = False
        map[x][y].block_sight = False
 
def create_v_tunnel(y1, y2, x):
    global map
    #vertical tunnel
    for y in range(min(y1, y2), max(y1, y2) + 1):
        map[x][y].blocked = False
        map[x][y].block_sight = False
 
def make_map():
    global map, player
 
    #fill map with "blocked" tiles
    map = [[ Tile(True)
        for y in range(MAP_HEIGHT) ]
            for x in range(MAP_WIDTH) ]
 
    rooms = []
    num_rooms = 0
 
    for r in range(MAX_ROOMS):
        #random width and height
        w = libtcod.random_get_int(0, ROOM_MIN_SIZE, ROOM_MAX_SIZE)
        h = libtcod.random_get_int(0, ROOM_MIN_SIZE, ROOM_MAX_SIZE)
        #random position without going out of the boundaries of the map
        x = libtcod.random_get_int(0, 0, MAP_WIDTH - w - 1)
        y = libtcod.random_get_int(0, 0, MAP_HEIGHT - h - 1)
 
        #"Rect" class makes rectangles easier to work with
        new_room = Rect(x, y, w, h)
 
        #run through the other rooms and see if they intersect with this one
        failed = False
        for other_room in rooms:
            if new_room.intersect(other_room):
                failed = True
                break
 
        if not failed:
            #this means there are no intersections, so this room is valid
 
            #"paint" it to the map's tiles
            create_room(new_room)

            #center coordinates of new room, will be useful later
            (new_x, new_y) = new_room.center()
 
            if num_rooms == 0:
                #this is the first room, where the player starts at
                player.x = new_x
                player.y = new_y
            else:
                #all rooms after the first:
                #connect it to the previous room with a tunnel
 
                #center coordinates of previous room
                (prev_x, prev_y) = rooms[num_rooms-1].center()
 
                #draw a coin (random number that is either 0 or 1)
                if libtcod.random_get_int(0, 0, 1) == 1:
                    #first move horizontally, then vertically
                    create_h_tunnel(prev_x, new_x, prev_y)
                    create_v_tunnel(prev_y, new_y, new_x)
                else:
                    #first move vertically, then horizontally
                    create_v_tunnel(prev_y, new_y, prev_x)
                    create_h_tunnel(prev_x, new_x, new_y)
             
            #add some contents to this room, such as monsters
            place_objects(new_room)
            
            #finally, append the new room to the list
            rooms.append(new_room)
            num_rooms += 1
 
 
def place_objects(room):
    #choose random number of monsters
    num_monsters = libtcod.random_get_int(0, 0, MAX_ROOM_MONSTERS)
 
    for i in range(num_monsters):
        #choose random spot for this monster
        x = libtcod.random_get_int(0, room.x1+1, room.x2-1)
        y = libtcod.random_get_int(0, room.y1+1, room.y2-1)

        #only place it if the tile is not blocked
        if not is_blocked(x, y):
            if libtcod.random_get_int(0, 0, 100) < 80:  #80% chance of getting an orc
                #create an orc
                fighter_component = Fighter(hp=10, defense=0, power=3, death_function=monster_death)
                ai_component = BasicMonster()
 
                monster = Object(x, y, 'o', 'orc', libtcod.desaturated_green,
                    blocks=True, fighter=fighter_component, ai=ai_component)
            else:
                #create a troll
                fighter_component = Fighter(hp=16, defense=1, power=4, death_function=monster_death)
                ai_component = BasicMonster()
 
                monster = Object(x, y, 'T', 'troll', libtcod.darker_green,
                    blocks=True, fighter=fighter_component, ai=ai_component)
 
            objects.append(monster)
 
    #choose random number of items
    num_items = libtcod.random_get_int(0, 0, MAX_ROOM_ITEMS)
 
    for i in range(num_items):
        #choose random spot for this item
        x = libtcod.random_get_int(0, room.x1+1, room.x2-1)
        y = libtcod.random_get_int(0, room.y1+1, room.y2-1)
 
        #only place it if the tile is not blocked
        if not is_blocked(x, y):
            #create a healing potion
            item_component = Item(use_function=cast_heal)
 
            item = Object(x, y, '!', 'healing potion', libtcod.violet, item=item_component)
 
            objects.append(item)
            item.send_to_back()  #items appear below other objects


def render_bar(x, y, total_width, name, value, maximum, bar_color, back_color):
    #render a bar (HP, experience, etc). first calculate the width of the bar
    bar_width = int(float(value) / maximum * total_width)
 
    #render the background first
    libtcod.console_set_default_background(panel, back_color)
    libtcod.console_rect(panel, x, y, total_width, 1, False, libtcod.BKGND_SCREEN)
 
    #now render the bar on top
    libtcod.console_set_default_background(panel, bar_color)
    if bar_width > 0:
        libtcod.console_rect(panel, x, y, bar_width, 1, False, libtcod.BKGND_SCREEN)
 
    #finally, some centered text with the values
    libtcod.console_set_default_foreground(panel, libtcod.white)
    libtcod.console_print_ex(panel, x + total_width / 2, y, libtcod.BKGND_NONE, libtcod.CENTER,
        name + ': ' + str(value) + '/' + str(maximum))
 
def get_names_under_mouse():
    global mouse
 
    #return a string with the names of all objects under the mouse
    (x, y) = (mouse.cx, mouse.cy)
 
    #create a list with the names of all objects at the mouse's coordinates and in FOV
    names = [obj.name for obj in objects
        if obj.x == x and obj.y == y and libtcod.map_is_in_fov(fov_map, obj.x, obj.y)]
 
    names = ', '.join(names)  #join the names, separated by commas
    return names.capitalize()
 
def render_all():
    global fov_map, color_dark_wall, color_light_wall
    global color_dark_ground, color_light_ground
    global fov_recompute
 
    if fov_recompute:
        #recompute FOV if needed (the player moved or something)
        fov_recompute = False
        libtcod.map_compute_fov(fov_map, player.x, player.y, TORCH_RADIUS, FOV_LIGHT_WALLS, FOV_ALGO)
 
        #go through all tiles, and set their background color according to the FOV
        for y in range(MAP_HEIGHT):
            for x in range(MAP_WIDTH):
                visible = libtcod.map_is_in_fov(fov_map, x, y)
                wall = map[x][y].block_sight
                if not visible:
                    #if it's not visible right now, the player can only see it if it's explored
                    if map[x][y].explored:
                        if wall:
                            libtcod.console_set_char_background(con, x, y, color_dark_wall, libtcod.BKGND_SET)
                        else:
                            libtcod.console_set_char_background(con, x, y, color_dark_ground, libtcod.BKGND_SET)
                else:
                    #it's visible
                    if wall:
                        libtcod.console_set_char_background(con, x, y, color_light_wall, libtcod.BKGND_SET )
                    else:
                        libtcod.console_set_char_background(con, x, y, color_light_ground, libtcod.BKGND_SET )
                    #since it's visible, explore it
                    map[x][y].explored = True
 
    #draw all objects in the list, except the player. we want it to
    #always appear over all other objects! so it's drawn later.
    for object in objects:
        if object != player:
            object.draw()
    player.draw()
 
    #blit the contents of "con" to the root console
    libtcod.console_blit(con, 0, 0, MAP_WIDTH, MAP_HEIGHT, 0, 0, 0)
 
 
    #prepare to render the GUI panel
    libtcod.console_set_default_background(panel, libtcod.black)
    libtcod.console_clear(panel)
 
    #print the game messages, one line at a time
    y = 1
    for (line, color) in game_msgs:
        libtcod.console_set_default_foreground(panel, color)
        libtcod.console_print_ex(panel, MSG_X, y, libtcod.BKGND_NONE, libtcod.LEFT, line)
        y += 1
 
    #show the player's stats
    render_bar(1, 1, BAR_WIDTH, 'HP', player.fighter.hp, player.fighter.max_hp,
        libtcod.light_red, libtcod.darker_red)
 
    #display names of objects under the mouse
    libtcod.console_set_default_foreground(panel, libtcod.light_gray)
    libtcod.console_print_ex(panel, 1, 0, libtcod.BKGND_NONE, libtcod.LEFT, get_names_under_mouse())
 
    #blit the contents of "panel" to the root console
    libtcod.console_blit(panel, 0, 0, SCREEN_WIDTH, PANEL_HEIGHT, 0, 0, PANEL_Y)
 
 
def message(new_msg, color = libtcod.white):
    #split the message if necessary, among multiple lines
    new_msg_lines = textwrap.wrap(new_msg, MSG_WIDTH)
 
    for line in new_msg_lines:
        #if the buffer is full, remove the first line to make room for the new one
        if len(game_msgs) == MSG_HEIGHT:
            del game_msgs[0]
 
        #add the new line as a tuple, with the text and the color
        game_msgs.append( (line, color) )
 
 
def player_move_or_attack(dx, dy):
    global fov_recompute
 
    #the coordinates the player is moving to/attacking
    x = player.x + dx
    y = player.y + dy
 
    #try to find an attackable object there
    target = None
    for object in objects:
        if object.fighter and object.x == x and object.y == y:
            target = object
            break
 
    #attack if target found, move otherwise
    if target is not None:
        player.fighter.attack(target)
    else:
        player.move(dx, dy)
        fov_recompute = True
 
 
def menu(header, options, width):
    if len(options) > 26: raise ValueError('Cannot have a menu with more than 26 options.')
 
    #calculate total height for the header (after auto-wrap) and one line per option
    header_height = libtcod.console_get_height_rect(con, 0, 0, width, SCREEN_HEIGHT, header)
    height = len(options) + header_height
 
    #create an off-screen console that represents the menu's window
    window = libtcod.console_new(width, height)
 
    #print the header, with auto-wrap
    libtcod.console_set_default_foreground(window, libtcod.white)
    libtcod.console_print_rect_ex(window, 0, 0, width, height, libtcod.BKGND_NONE, libtcod.LEFT, header)
 
    #print all the options
    y = header_height
    letter_index = ord('a')
    for option_text in options:
        text = '(' + chr(letter_index) + ') ' + option_text
        libtcod.console_print_ex(window, 0, y, libtcod.BKGND_NONE, libtcod.LEFT, text)
        y += 1
        letter_index += 1
 
    #blit the contents of "window" to the root console
    x = SCREEN_WIDTH/2 - width/2
    y = SCREEN_HEIGHT/2 - height/2
    libtcod.console_blit(window, 0, 0, width, height, 0, x, y, 1.0, 0.7)
 
    #present the root console to the player and wait for a key-press
    libtcod.console_flush()
    key = libtcod.console_wait_for_keypress(True)
 
    #convert the ASCII code to an index; if it corresponds to an option, return it
    index = key.c - ord('a')
    if index >= 0 and index < len(options): return index
    return None
 
def inventory_menu(header):
    #show a menu with each item of the inventory as an option
    if len(inventory) == 0:
        options = ['Inventory is empty.']
    else:
        options = [item.name for item in inventory]
 
    index = menu(header, options, INVENTORY_WIDTH)
 
    #if an item was chosen, return it
    if index is None or len(inventory) == 0: return None
    return inventory[index].item
 
def handle_keys():
    global key;
 
    if key.vk == libtcod.KEY_ENTER and key.lalt:
        #Alt+Enter: toggle fullscreen
        libtcod.console_set_fullscreen(not libtcod.console_is_fullscreen())
 
    elif key.vk == libtcod.KEY_ESCAPE:
        return 'exit'  #exit game
 
    if game_state == 'playing':
        #movement keys
        if key.vk == libtcod.KEY_UP:
            player_move_or_attack(0, -1)
 
        elif key.vk == libtcod.KEY_DOWN:
            player_move_or_attack(0, 1)
 
        elif key.vk == libtcod.KEY_LEFT:
            player_move_or_attack(-1, 0)
 
        elif key.vk == libtcod.KEY_RIGHT:
            player_move_or_attack(1, 0)
        else:
            #test for other keys
            key_char = chr(key.c)
 
            if key_char == 'g':
                #pick up an item
                for object in objects:  #look for an item in the player's tile
                    if object.x == player.x and object.y == player.y and object.item:
                        object.item.pick_up()
                        break
 
            if key_char == 'i':
                #show the inventory; if an item is selected, use it
                chosen_item = inventory_menu('Press the key next to an item to use it, or any other to cancel.\n')
                if chosen_item is not None:
                    chosen_item.use()
 
            return 'didnt-take-turn'
 
def player_death(player):
    #the game ended!
    global game_state
    message('You died!', libtcod.red)
    game_state = 'dead'
 
    #for added effect, transform the player into a corpse!
    player.char = '%'
    player.color = libtcod.dark_red
 
def monster_death(monster):
    #transform it into a nasty corpse! it doesn't block, can't be
    #attacked and doesn't move
    message(monster.name.capitalize() + ' is dead!', libtcod.orange)
    monster.char = '%'
    monster.color = libtcod.dark_red
    monster.blocks = False
    monster.fighter = None
    monster.ai = None
    monster.name = 'remains of ' + monster.name
    monster.send_to_back()
 
def cast_heal():
    #heal the player
    if player.fighter.hp == player.fighter.max_hp:
        message('You are already at full health.', libtcod.red)
        return 'cancelled'
 
    message('Your wounds start to feel better!', libtcod.light_violet)
    player.fighter.heal(HEAL_AMOUNT)
 
#############################################
# Initialization & Main Loop
#############################################
 
libtcod.console_set_custom_font('arial10x10.png', libtcod.FONT_TYPE_GREYSCALE | libtcod.FONT_LAYOUT_TCOD)
libtcod.console_init_root(SCREEN_WIDTH, SCREEN_HEIGHT, 'python/libtcod tutorial', False)
libtcod.sys_set_fps(LIMIT_FPS)
con = libtcod.console_new(MAP_WIDTH, MAP_HEIGHT)
panel = libtcod.console_new(SCREEN_WIDTH, PANEL_HEIGHT)
 
#create object representing the player
fighter_component = Fighter(hp=30, defense=2, power=5, death_function=player_death)
player = Object(0, 0, '@', 'player', libtcod.white, blocks=True, fighter=fighter_component)
 
#the list of objects with just the player
objects = [player]
 
#generate map (at this point it's not drawn to the screen)
make_map()
 
#create the FOV map, according to the generated map
fov_map = libtcod.map_new(MAP_WIDTH, MAP_HEIGHT)
for y in range(MAP_HEIGHT):
    for x in range(MAP_WIDTH):
        libtcod.map_set_properties(fov_map, x, y, not map[x][y].block_sight, not map[x][y].blocked)
 
fov_recompute = True
game_state = 'playing'
player_action = None
 
inventory = []
 
#create the list of game messages and their colors, starts empty
game_msgs = []
 
#a warm welcoming message!
message('Welcome stranger! Prepare to perish in the Tombs of the Ancient Kings.', libtcod.red)
 
mouse = libtcod.Mouse()
key = libtcod.Key()
 
while not libtcod.console_is_window_closed():
 
    #render the screen
    libtcod.sys_check_for_event(libtcod.EVENT_KEY_PRESS|libtcod.EVENT_MOUSE,key,mouse)
    render_all()
 
    libtcod.console_flush()
 
    #erase all objects at their old locations, before they move
    for object in objects:
        object.clear()
 
    #handle keys and exit game if needed
    player_action = handle_keys()
    if player_action == 'exit':
        break
 
    #let monsters take their turn
    if game_state == 'playing' and player_action != 'didnt-take-turn':
        for object in objects:
            if object.ai:
                object.ai.take_turn()